Aortic Dissection Incidence and Risk Factor Analysis: Findings from the China Kadoorie Biobank.

Objective: Data on the incidence of aortic dissection (AD) from population based prospective studies are scarce and its risk factors are not well studied in China. The aim of this study was to investigate the relatively accurate incidence of AD in ten regions of China and to identify its potential risk factors using a population based prospective study.

Methods: Data from a prospective cohort study involving ∼510 000 middle aged adults in ten regions of China from 2004 - 2008 (the China Kadoorie Biobank) were used. The incidence of AD was calculated and the association between potential risk factors (body mass index [BMI], hypertension, and diabetes) and the occurrence of AD was evaluated using competing risk analysis.

Results: The study included 512 724 participants (59.0% female, median age 51.5 years). During a median follow up of 121 months, 119 participants developed AD. The incidence of AD was 2.35 (95% confidence interval [CI] 1.93 - 2.77), 3.97 (95% CI 3.10 - 4.83), and 1.25 (95% CI 0.86 - 1.65) per 100 000 person years for the whole cohort, male participants, and female participants, respectively. Competing risk analysis identified female sex (hazard ratio [HR] 0.35, 95% CI 0.24 - 0.52; p < .001) and hypertension (HR 6.21, 95% CI 3.94 - 9.80; p < .001) as independent predictors of AD. BMI, diabetes, and random blood glucose were not associated with AD.

Conclusion: In contrast to previous data and clinical observations, there was no significant correlation between diabetes (or random blood glucose) or BMI and the occurrence of AD. Male sex and hypertension were independently associated with the occurrence of AD.